A planar inverted-F antenna-based chemical sensor for ion concentrations

The development of new wireless sensing devices could provide significant opportunities for medical and environmental applications. A planar inverted-F antenna (PIFA) is a typical antenna that is widely used in communications. Here, we report here a PIFA for chemical sensing of ion concentrations. When the ion concentration increases, the reflection coefficient of the antenna decreases accordingly. The PIFA sensor shows a linear detection range from 0.15 μM to 15 μM. We expect that this study could offer exciting opportunities for fundamental studies as well as applications of wireless antennas for chemical and biological sensing, and advance related healthcare and environmental applications.